Thread supply device for textile machines

ABSTRACT

A thread supply device for a textile machine, comprises a thread drum upon which the thread can be wound tangentially and a thread control element which can be moved into two positions, the thread being axially unwound at a speed independent of the winding speed in the first position (intermittent thread supply) and the unwinding speed being limited to the winding speed in the second position (positive thread supply). A switch is actuatable by the thread control element for continuously actuating the winding drive in the case of positive thread supply. During intermittent thread supplying, a sensing element monitors the thread storage located on the thread drum and disconnects the winding drive when a maximum amount of thread has been attained on the thread drum. The switch is constructed as an electrical double-throw switch which assumes a first switching position during intermittent thread supply and a second switching position during positive thread supply. The sensing element is switched into a route by means of the double-throw switch during positive thread supply such that a control circuit of the machine drive of the textile machine, which circuit is connected to said route, is caused to de-energize the machine drive when the thread storage on the thread drum exceeds a maximum value and/or falls below a minimum value.

United States Patent Jacobsson 1 Nov. 4, 1975 1 THREAD SUPPLY DEVICE FOR TEXTILE MACHINES [57 ABSTRACT [75] Inventor: Kurt Arne Gunnar Jacobsson,

Ulricehamn, Sweden {73] Assignee: Aktiebolaget IRO, Ulricehamn,

Sweden [22] Filed: Mar. 8, 1974 [21] Appl. No; 449,259

[30] Foreign Application Priority Data Mar. 16, 1974 Germany 2313274 [52] US. Cl. 340/259; 66/163; 139/336 [51] Int. Cl. G08B 21/00; D048 35/12 [58] Field of Search 340/259; 139/336, 353; 66/163 [56] References Cited UNITED STATES PATENTS 3,159,123 12/1964 Godwin et a1, 139/353 3,345,812 10/1967 Pickering l t 340/259 3,562,734 2/1971 Hotchkiss 340/259 3,793,929 3/1974 Balgalvis 66/163 Primary ExaminerGlen R. Swann, IIl Attorney, Agent, or Firm-Woodhams, Blanchard and Flynn THREAD DRUM OONTROL CIRCUIT\ 26 A thread supply device for a textile machine, comprises a thread drum upon which the thread can be wound tangentially and a thread control element which can be moved into two positions, the thread being axially unwound at a speed independent of the winding speed in the first position (intermittent thread supply) and the unwinding speed being limited to the winding speed in the second position (positive thread supply). A switch is actuatable by the thread control element for continuously actuating the winding drive in the case of positive thread supply. During intermittent thread supplying, a sensing element monitors the thread storage located on the thread drum and disconnects the winding drive when a maximum amount of thread has been attained on the thread drum. The switch is constructed as an electrical double-throw switch which assumes a first switching position during intermittent thread supply and a second switching position during positive thread supply. The sensing element is switched into a route by means of the doublethrow switch during positive thread supply such that a control circuit of the machine drive of the textile ma chine, which circuit is connected to said route, is caused to de-energize the machine drive when the thread storage on the thread drum exceeds a maximum value and/or falls below a minimum value.

10 Claims, 5 Drawing Figures US. Patent Nov. 4, 1975 Sheet 1 of3 3,918,036

US. Patent Nov. 4, 1975 Sheet 2 of3 Fig. 2a

THREAD DRUM CONTROL cmcung 25 7 THREAD DRUM Fig. 2b

THREAD SUPPLY DEVICE FOR TEXTILE MACHINES FIELD OF THE INVENTION This invention relates to a thread supply device for textile machines, comprising a thread drum upon which the thread can be wound tangentially and further comprising a thread control element which can be moved into two positions, the thread being axially unwound at a speed independent of the winding speed in said first position (intermittent thread supply) and the unwinding speed being limited to the winding speed in said second position (positive thread supply), further comprising a switch actuatable by said thread control element for continuously actuating the winding drive in the case of positive thread supply, further comprising a sensing element which monitors the thread storage located on the thread drum and which disconnects the winding drive during intermittent thread supply when a maximum amount of thread has been attained on the thread drum.

BACKGROUND OF THE INVENTION A basic difference is made between two kinds of thread supply in the case of textile machines. In one case, the textile machine can unwind the thread at an unlimited speed from the thread drum of the thread suppiy device. In this case, care should be taken in seeing that sufficient thread storage is present on the thread drum, which is achieved in that the thread stor age on the drum is continuously monitored and the winding drive is energized when a predetermined minimum thread storage is reached and remains energized until a predetermined maximum thread storage is attained. In so doing, the winding drive must be designed such that the winding speed is greater than the maximum average unwinding speed of the thread. This kind of thread supply in textile machines is designated hereinafter as intermittent thread supply. It is employed in all cases where the thread consumption in the textile machine varies greatly from time to time. This is the case for instance in the case of Jacquard machines, Cotton machines, flat bed knitting machines, stocking knitting machines, bobbin machines, warp maclfines and weaving looms of various types. This type of thread supply is also desirable if the thread is supposed to be pulled when the textile machine is standing still or is moved manually, for example, for carrying out adjust ment or repair work. In many textile machines, what is known as plain goods or smooth goods, are produced and the thread is processed at a constant speed during this manufacturing process. This type of thread supply, in which the thread drum winds up the thread at the same speed at which the thread is unwound, is termed positive thread supply.

German published application No. DAS 1,760,600 reveals a thread supply device in which a thread control element is provided which can be moved from a first position, in which it does not impair the free removal of the thread from the thread drum, into a second position, in which it limits the speed at which the thread is unwound from the thread drum to the speed at which it is wound up. In one embodiment, the thread control element is movable disposed so that only an axial thread withdrawal is possible in the first position and only tangential thread removal from the thread drum was possible in the second position. A sensing element is provided in this thread supply device for the intermittent thread supply mode and monitors the thread storage on the thread drum and actuates the winding drive via a switching device associated with the sensing element when a minimum thread storage has been reached. Since the winding drive must be in continuous operation during positive thread supply, the thread control element is mechanically coupled to a switch which maintains the winding drive in continuous operation during positive thread supply.

If such a thread supply device is employed for positive thread supply, the following problem results: occasional breaks in the thread which is supplied to the drum cannot be avoided. In practice. a thread monitor which discontinues the machine drive of the textile ma chine when the thread breaks is provided in the path of the thread. Since such a discontinuation or shutdown of the machine is not immediate due to the inertia of the textile machine. the machine still continues to operate even after the drive means has been switched off. The operating elements of the textile machine thus continue to unwind some thread from the thread storage on the drum without simultaneously winding a corresponding amount of thread onto this drum. The fact that a sufficient amount of thread can still be unwound from the thread drum when a break in the thread occurs at the thread infeed prevents a loose end from being pulled into a textile commodity to be manufactured. By repeatedly unwinding such an amount of thread without replacing the thread storage on the thread drum, this storage is gradually exhausted so that an end of the thread is pulled into the commodity after several breaks resulting in a faulty commodity. It was therefore suggested in my earlier application Ser. No. 309,288 (which corresponds to German application No. P 2| 59 now U.S. Pat. No. 3,791,599, to monitor the thread storage located on the thread drum and to deactivate the machine drive of the textile machine when the thread storage falls below a predetermined value.

Just as the thread storage is not supposed to fall below a certain minimum amount during positive thread supply, it is also desirable that a predetermined maximum thread storage not be exceeded either. If too much thread storage is located on the thread drum, the thread cannot be unwound with the required constant thread tension.

The invention is based on the object of proposing a thread supply device of the type cited at the outset for preventing in an easy and simple manner that a predetermined maximum thread storage is not exceeded and- /or that the thread storage does not fall below a predetermined minimum value.

This object is accomplished in accordance with the invention in that the switch is constructed as an electrical doublethrow switch which assumes a switching position I during intermittent thread supply and a switching position [I during positive thread supply, that the sensing element is switched into a route by means of the double-throw switch during positive thread supply such that a control circuit of the machine drive of the textile machine, which circuit is connected to said route, is caused to de-energize the machine drive when the thread storage on the thread drum exceeds a maximum value and/or falls below a minimum value.

In comparison to the thread supply device disclosed in abovementioned German published application DAS 1,760,600 in which the thread control element is directly coupled by mechanical means to the switching ing it possible in a simple and easy manner either not to actuate the machine drive during positive thread supply or to shut it off automatically when the thread storage on the thread drum either exceeds a maximum value or falls below a minimum value. Continuous actuation of the winding drive, which is required simultaneously during transition from intermittent to positive thread supply, is also achieved by means of the double-throw switch. By employing a double-throw switch coupled to the thread control element it is thus possible to convert from intermittent to positive thread supply, the sensing element having the following function during the second mode of operation: to monitor the thread storage on the thread drum and to switch off the machine drive of the textile machine when a specific amount of storage is exceeded or fallen below.

A preferred embodiment of a thread supply device, in which the machine drive is de-energized during positive thread supply when the maximum storage is exceeded, is given in that the sensing element contains a switch which is connected in series with the doublethrow switch, and this series circuit formed by the switch and by the first route of the double-throw switch when the route is closed in switching position I is connected to the circuit of a control circuit for the winding drive during intennittent thread supply, said control circuit de-energizing the winding drive when the switch is closed, and that the switch is connected to the control circuit for the machine drive during positive thread supply via the second route formed when the doublethrow switch is in switching position ll. This embodiment of the thread supply device prevents operation during positive thread supply with too large a thread storage on the thread drum which would have the drawback that the required accuracy of the thread tension of the unwound thread could not be maintained. Too great a thread storage can be formed, for example, when too much thread is wound manually onto the drum by mistake during repair work. In addition, such an embodiment of the thread control element, which merely prevents the thread unwinding speed from exceeding the thread winding speed, but does not prevent the thread unwinding speed falling below the thread winding speed, makes it possible that the thread storage grows continuously during positive thread supply operation so that preventative measures are necessary to de-energize the machine drive when a thread storage which is still admissible is exceeded on the thread drum. The switching device of the invention makes this possible in a simple way.

Another advantage of this embodiment can be seen in the fact that unintentional activation of operation during positive thread supply very quickly leads to shut-down of the machine drive when the thread supply device was supposed to operate intermittently. This is due to the fact that the winding drive is operated during intermittent thread supply at a considerably higher speed than during positive thread supply. Since the winding drive is in continuous operation when the double-throw switch is in position ll, the maximum admissible thread storage is very quickly achieved on the thread drum when the machine is turned on, thereby causing the machine drive to be shut off.

In another advantageous embodiment, the invention provides that the thread control element is designed as a thread hook which can be pivoted into the path of movement of the thread which is unwound from the thread drum in axial direction, said hook having an open end such that the thread is caught in the hook during the mode of operation in which the unwinding speed exceeds the winding speed. In the case of the prior art described at the outset, the thread control element is constructed as a thread eye in which the thread must be introduced during a transition from intermittent to positive thread supply. The afore-cited hookshaped thread control element, on the other hand, has the essential advantage that it is not necessary to insert the thread into the hook because the thread is caught automatically when rotating in its path of movement. This prevents the thread unwinding speed exceeding the thread winding speed. However, there is still a possibility that the thread unwinding speed will fall below the thread winding speed because the thread control element limits the movement of the thread in only one direction and not in the other. A continuous increase in the thread storage during positive operation occurs, for example, when the thread transporting means of the textile machine is dirty, thereby reducing the thread tension between the thread supply device and the place of use and the thread is not used in the amount predicted.

in another advantageous embodiment of a thread supply device, in which the machine drive is deactivated during positive thread supply when the thread storage falls below a minimum value, the invention provides that the sensing element is designed as a switch in series with the double-throw switch, that this series circuit formed by the switch and by the first route of the double-throw switch when the route is closed in switching position I is connected to a control circuit for the winding drive during intermittent thread supply, said control circuit tie-energizing the winding drive when the switch is open, and that the switch is connected to the control circuit for the machine drive during positive thread supply via the second route formed when the double-throw switch is in switching position II. In this thread supply device, the invention prevents a loose end of the thread from being drawn into the textile product because the necessary minimum thread storage is no longer present on the thread drum when a break in the thread occurred.

A preferred embodiment of a thread supply device is given in that two sensing elements are provided for shutting down the machine drive of the textile machine when the maximum thread storage is exceeded and when the thread storage falls under the minimum value during positive thread supply, said first sensing element responding when the maximum value is achieved and said second sensing element responding when the minimum thread storage is reached and that only one sensing element is connected to the winding drive during intennittent thread supply by means of the doublethrow switch. This embodiment has the considerable advantage that the thread storage is prevented from both falling below a minimum value and from exceeding a maximum value without complicating the transition operation for moving the thread control element from the one into the other position, which operation must be executed by hand. Moreover, the cited con structive solution is very easy and merely necessitates a second sensing element.

A preferred embodiment consists in that the doublethrow switch is constructed with two poles, that the sensing elements each contain a switch and that during positive thread supply the series circuit respectively consisting of a switch and a route of the double-throw switch which is closed in this mode of operation is connected in parallel and this parallel circuit is in series with the control circuit for the machine drive of the textile machine. By employing a twopoled doublethrow switch in parallel with the two switches of the sensing elements during positive thread supply, the invention provides a device which is very simple in construction for shutting off the machine drive both when the thread storage exceeds the maximum value as well as when it falls below a minimum value.

It is also advantageous if a thread monitor is provided at the thread inlet and/or the thread outlet and is coupled to a switch which can be closed when a break in the thread occurs and which is connected in parallel to the series circuit formed by the switch of the thread sensing element and' by the route of the double-throw switch which is closed in switching position I. The thread monitors, which are normally provided at the thread inlet and outlet, can be readily accommodated in the switching device without additional means in the manner disclosed.

A favorable embodiment provides that the control circuit of the machine drive is formed by a relay which maintains the machine drive in operation during a currentless state. A relay which offers the possibility of continuously keeping the machine drive in operation during a currentless state is especially suitable, particularly in light of the fact that the individual switches (thread monitors and sensing element switches) which shut down the machine drive are connected in series.

It is also advantageous that a signal light is provided on the thread supply drive which lights up when the machine drive is de-energized. In a textile machine, a plurality of thread supply devices are normally used at one time. A signal light on each thread supply device permits an error, which has occurred in the thread supply device, to be localized and eliminated very quickly.

An advantageous circuit arrangement is obtained in that the signal light is connected in a circuit which contains the switch of the sensing element, the route of the double-throw switch, said route being closed in switching position II, and a source of current.

Another advantageous embodiment consists of a diode for isolating the signal lights of a plurality of thread supply devices connected to the machine drive. This diode provided in each thread supply device prevents in a simple manner several signal lights lighting up when the machine drive is de-energized due to an error occurring in a thread supply device. When several signal lights are activated at once, the search for the error is greatly complicated.

BRIEF DESCRIPTION OF THE DRAWINGS The invention will now be more fully described with reference to a number of embodiments illustrated in the drawing in which:

FIG. 1 is a schematic side elevation of an inventive thread supply device comprising a circuit arrangement schematically illustrated therein as corresponds essentially to the circuit arrangement shown in FIG. 2a;

FIG. 2a is a first embodiment of an inventive circuit arrangement for a thread supply device shown in FIG. I in which the machine drive is de-energized when a maximum thread storage is exceeded;

FIG. 2b is another circuit diagram in which the machine drive is de-energized when the thread storage falls below a minimum value;

FIG. 3 is another embodiment of an inventive circuit arrangement in which the machine drive is de-energized when the thread storage exceeds a maximum value or falls below a minimum value, and

FIG. 4 is a circuit arrangement which shows the interconnection of a plurality of circuit arrangements respectively associated with more than one thread supply device.

DETAILED DESCRIPTION The thread supply device illustrated in FIG. 1 contains a thread drum 2 which is rotatable about a vertical axis in a stationary frame 1. The thread drum 2 is movable via a belt drive 3 which can be engaged and disengaged via a clutch 4. A sliding ring 5 which can be pivoted about a horizontal axis and which continuously pushes the thread skein 6 located on the drum in a downward direction due to spring action exerted in this direction is located on the thread drum 2. An on-ofi switch 7 is connected mechanically to the sliding ring 5. A thread control element 9 is secured to a support arm 8 which in turn is secured to the frame 1 and which can be moved laterally along the thread drum. The free end of said control element 9 projects into the path of movement of the unwinding thread in the position in the drawing. The end is designed in the shape of a hook which catches the thread 10 in its path of movement as it is withdrawn from the drum 2. The thread control element 9 can be pivoted from .the position shown in the drawing into the plane of the drawing and, in this position, is completely moved out of the path of movement of said thread 10. A double-throw switch 11 is connected mechanically to the thread control element 9. The double-throw switch 1 1 assumes switching position II when the thread control element is in the illustrated position and assumes switching position I when the element 9 is moved out of the path of movement of the thread. A thread monitor 12 is disposed on the rotational axis of the thread drum 2 and is connected to an on-off switch 14 via an arm 13. A signal light 15 is provided on the support arm 8 to indicate a misfunction. The thread supply device can be connected to a machine drive controlling a textile machine via a plug device 16 on the frame 1.

The thread supply device shown in FIG. I operates with positive thread supply when the thread control element 9 is position as seen in the drawing. Since the thread discharge is maintained in a fixed position relative to the stationary frame 1 by means of the thread control element 9, only that amount of thread is removed from the thread drum 2 which is simultaneously wound on the drum at the same time. This ensures that the thread storage 6 on the thread drum 2 remains constant if the exceptional case mentioned above is disregarded, namely that the unwinding speed is lower than the winding speed which can be the case when the unwinding thread rotates together with the thread drum 2 and the thread control element 9 is passed" or overrun by the thread in a direction facing away from the hooklike end. When the thread control element 9 is in the second position in which it is moved out of the path of the thread, the thread supply device operates with intermittent thread supply. In so doing, the winding-on speed of the thread is considerably higher than the im mediate unwinding speed. The thread drum 2, how ever, is not continuously coupled to the belt drive 3 in this mode of operation. The clutch 4 is controlled in this case by the position of the switch 7 which is connected to the sliding ring 5. Instead of the belt drive 3 shown in the drawing, an electromotor can also be provided for intermittent thread supply. This electromotor is directly connected to the thread drum 2 and can be switched on and off via the switch 7.

The electrical circuit shown in the thread supply device according to FIG. I is expediently explained with reference to the somewhat simplified circuit diagram in accordance with FIG. 2a. The same parts in the figures have been provided with the same reference numbers for purposes of clarification. The circuit diagram illustrated in FIG. 2a shows a machine drive 20, such as a motor, for the textile machine which can be connected to a power supply source 22 by switching contacts 21 of a relay 21. The relay 21 is connected in a circuit which is provided with energy via a transformer 23. With the exception of the relay 21 and the transformer 23, all structural elements of the circuit arrangement which will be described hereinbelow are arranged in the thread supply device and are connected to the relay 21 and the transformer 23 via the plug device 16 which can be seen in FIG. I. In this circuit arrangement, the double-throw switch 11 is connected in series with the switch 7 which is mechanically connected to the sliding ring 5. In switching position II of the double-throw switch 11 which is associated with positive thread supply, two further on-off switches 14 and 24 are connected in parallel to switch 7 and are associated with a thread monitor at the thread inlet and outlet of the thread supply device. This parallel circuit of switches 7, l4 and 24 is connected in series to the relay 21 via a diode 25. The series circuit formed by the relay 2I and the diode 25 is parallel to the signal light 15. The control circuit 26 which is additionally contained in the circuit diagram for the winding drive is dead when the double-throw switch 11 is in switching position II.

The following is intended to explain the mode of function of the circuit arrangement according to FIG. 2a, attention first being devoted to positive thread supply in which the throw switch 11 is in position II. It is assumed that switches 7, l4 and 24 are all open so that the relay 21 is dead. When the relay is in this switching position, the switching contacts 21' are closed and the machine drive of the textile machine is connected to the energy supply source 22, i.e. it is in operation. Since there is no voltage drop in the series circuit formed by the relay 21 and the diode 25 when the relay is dead, the signal light 15 does not burn either. The control circuit 26 for the winding drive, said circuit being dead when the double-throw switch 11 is in position II, actuates the winding drive so that the thread drum 2 is in continuous motion. If all three switches 7, l4 and 24 are opened, no malfunction occurs in the thread supply device with which these three switches are associated. By closing one or more of the switches 7, I4 and 24, the relay 21 is energized and the machine drive is deactivated due to opening of relay switch 21'. At the time, the signal light 15 lights up due to the voltage drop in the relay and in the diode 2S. Switches I4 and 24 are closed by a break in the thread which occurs at the outlet or inlet respectively, of the thread supply device. The switch 7 is closed when a predetermined maximum thread storage 6 is exceeded on the thread drum 2.

When the double-throw switch 11 is switched to intermittent operation, and with switch 7 open, the machine drive 20 is in operation since relay 21 is de-energized. On the contrary, when the switch 7 is closed, the control circuit 26 for the winding drive is energized, thereby disconnecting the winding drive until the thread storage 6 on the thread drum 2 has been reduced to a lower limit which then opens the switch 7 again. The functions of the switches 14 and 24 which are associated with the thread monitors are not impaired by switching the double-throw switch 11.

The recited circuit arrangement according to FIG. 2a for disconnecting the machine drive 20 when a maximum thread storage 6 on the thread drum has been exceeded can be modified very easily so that the machine drive 20 is discontinued when the thread storage falls below a minimum value. It is necessary that the switch 7 be connected to the sliding ring 5 such that it is closed when the thread storage falls below the predetennined minimum value. In doing so, it is also necessary to rearrange the control circuit 26 for the winding drive so that it actuates the winding drive when the switch 7 is closed. In order that the winding drive is actuated even when the double-throw switch Ila is in position I] during positive thread supply, the double-throw switch 1 la must be designed with two poles and must energize the winding drive via the second pole when located in switching position ll. These changes are illustrated in FIG. 2b.

The circuit arrangement illustrated in FIG. 3 contains another switch 30 as compared to the circuit diagram shown in FIG. 2a. The switch 30 is connected to the sliding ring 5 such that it is closed when the thread storage 6 on the thread drum 2 falls below a minimum, whereas switch 7 is closed when the thread storage exceeds a preselected maximum. Switches 7 and 30 are connected to a twopole double-throw switch Ila and are connected in parallel to one another when the double-throw switch is in position II as well as being connected in parallel to switches 14 and 24 of the thread monitors. When the double throw switch 11a is in switching position I, only switch 7 is connected to the control circuit 26 of the winding drive and disconnects the same when the maximum thread storage is exceeded. However, when switch Ila is in the positive thread feeding position II, both switches 7 and 30 are connected to the control circuit 26 so as to deactivate the machine drive 20 in the event either switch 7 or 30 is closed due to the thread supply being above or below the predetermined maximum and minimum respectively. Thus, switches 7 and 30 deactivate the machine drive during positive thread supply when the the thread on the drum exceeds a preselected amount which may be either a preselected maximum or preselected minimum value.

FIG. 4 shows how two thread supply devices, which are constructed according to the circuit diagram of FIG. 2a, are interconnected. They are switched in parallel via the respective diodes 25 and 25' and the terminal ends of the signal lights 15 and 15' remote from said diodes as can be seen from this circuit diagram. This also indicates the function of the diodes 25 and 25' which prevent any lights other than the associated signal lights 15 or 15' from lighting up when a set of switches fonned from switches 7, l4 and 24 of 7', l4

and 24' are activated, since a diode would have to be traversed in the reverse direction in this case. Of course, the variations illustrated in the circuit diagrams according to FIG. 2b and FIG. 3 can also be realized with this interconnection. An arbitrary number of thread supply devices can be connected to one and the same relay in a manner similar to how the second thread supply device is connected in this case. The relay itself is continuously traversed by the same current even when switches in an arbitrarily large number of thread supply devices are activated and, for this reason, cannot be overloaded by a large number of thread supply devices.

The control circuit 26 for the winding drive is shown in different embodiments in the circuit arrangements according to FIG. 2a and 2b. Whereas in the circuit arrangement according to FIG. 2a the winding drive is only activated when the control circuit is dead, the drive is activated in the circuit arrangement according to FIG. 2b only when the control circuit is live.

The control circuit 26 according to FIG. can also be realized as a magnetic clutch which releases the winding drive from the thread drum when the control circuit is energized. In the circuit arrangement according to FIG. 2b, the motor of a winding drive could directly replace the control circuit 26. The control circuit could also be constructed as a relay whose switching contacts, which actuate the winding drive, are closed when the relay is live or dead according to the case at hand.

What is claimed is:

I. In a thread supply device for a textile machine having a drive, the thread supply device including a thread drum to which the thread may be supplied tangentially, a winding drive for loading the thread on the drum, a thread control element which is movable into first and second positions, in which first position the thread is removable axially of the drum at a speed independent of the winding speed so as to permit intermittent thread supply and in which second position the removal speed of the thread from the drum is limited to the winding speed so as to permit positive thread supply, switch means actuable by said thread control element for continuously actuating the winding drive when said control element is in the second position, and sensing means for monitoring the thread supply on the thread drum and for disconnecting the winding drive when the control element is in the first position and a preselected amount of thread is present on the thread drum, comprising the improvement wherein the switch means is an electrical double-throw switch which is disposed in a first switching position during intennittent thread supply and is disposed in a second switching position during positive thread supply, and said sensing means being switched into a circuit by means of the doublethrow switch during positive thread supply such that a control circuit causes deenergization of the machine drive when the thread storage on the thread drum differs in one direction from the preselected amount.

2. A thread supply device according to claim I, in which the preselected amount comprises a preselected maximum thread storage so that the machine drive is deenergized during positive thread supply when the preselected maximum thread storage is exceeded, the sensing means containing a sensing switch connected in series with the double-throw switch, the series circuit fonned from the sensing switch and from the first route of the double throw switch when same is in said first switching position during intermittent thread supply being connected to a thread drum control circuit for the winding drive, said thread drum control circuit deenergizing the winding drive when the double throw switch is in said first switching position and the sensing switch is closed due to the thread supply on the drum exceeding said maximum thread storage, and the series circuit formed from the sensing switch and from a second route of the double-throw switch when same is in said second switching position during positive thread supply being connected to the control circuit of the machine drive whereby the machine drive is deenergized due to closing of said sensing switch when the thread supply on said drum exceeds said preselected maximum thread storage.

3. A thread supply device according to claim 2, wherein the thread control element is designed as a thread hook which can be pivoted into the path of movement of thread which is unwound from the drum in the axial direction thereof, said hook having an opened end such that the thread is caught in the hook during positive thread supply from the drum.

4. A thread device according to claim 1, in which the preselected amount comprises a preselected minimum thread storage so that the machine drive is deactivated during positive thread supply when the thread supply falls below said preselected minimum thread storage, the sensing means containing a sensing switch connected in series with the double-throw switch, the series circuit formed from the sensing switch and from the first route of the double-throw switch when same is in said first switching position during intermittent thread supply being connected to a thread drum control circuit for the winding drive, said thread drum control circuit energizing the winding drive when the double-throw switch is in said first switching position and the sensing switch is closed due to the thread supply on the drum falling below said minimum thread storage, and the series circuit formed from the sensing switch and from a second route of the double-throw switch when same is in said second switching position during positive thread supply being connected to the control circuit of the machine drive whereby the machine drive is deenergized due to closing of said sensing switch when the thread supply on said drum falls below said minimum thread storage.

5. A thread supply device according to claim 1, wherein said preselected amount comprises both a preselected maximum thread storage and a preselected minimum thread storage, said sensing means including a first sensing switch which responds when the maximum thread storage is obtained on the drum and a second sensing switch which responds when the minimum thread storage is obtained on the drum, only one of said sensing switches being connected in series with a first route of the double-throw switch when same is in said first switching position, said first route being connected to the winding drive, and both of said sensing switches being connected in series with a second route of the double throw switch when same is in the second switching position during positive thread supply, the second route of the doublethrow switch being interconnected to the machine drive so as to deenergize the machine drive when the thread storage on the drum exceeds or falls below the maximum or minimum thread storage, respectively.

6. A thread supply device according to claim 5, wherein the double-throw switch includes two poles,

1 l first and second sensing switches being disposed in parallel and each connected in series with one of said poles, and the two parallel circuits formed by said sensing switches each being connected in series with the control circuit for the machine drive when the doublethrow switch is in said second switching position.

7. A thread supply device according to claim 1, including thread monitor means associated with the thread which is being unwound from said drum for sensing a breakage in said thread, said thread monitor means including a monitoring switch which is closed when a break in the thread occurs, said monitoring switch being interconnected to the machine drive for deenergizing same when the monitoring switch is closed.

8. A thread supply device according to claim 1, including thread monitor means associated with the 12 thread which is being wound onto said drum for sensing a breakage in said thread, said thread monitor means including a monitoring switch which is closed when a break in the thread occurs, said monitoring switch being interconnected to the machine driven for deenergizing same when the monitoring switch is closed.

9. A thread supply device according to claim 1, wherein the control circuit for the machine drive is formed by a relay which maintains the machine driven in operation so long as the relay is in a currentness state.

10. A thread supply device according to claim 1, including signal light means energizable when the machine drive is deenergized, the signal light being connected in circuit with the double-throw switch when same is in the second switching position.

UNITED STATES PATENT AND TRADEMARK OFFICE CERTIFICATE OF CORRECTION PATENT NO. I 3 918 036 D T 3 November 4 1975 |NVENTOR( 1 Kurt Arne Gunnar Jacobsson It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

In the left column of the title page, after the heading "Foreign Application Priority Data, the correct priority date should be -March 16, l973-.

Column 10, line 23; the phrase "thread device" should read thread supply device-.

Column ll, line 1; before "first" insert -said---.

Column 12, line 5; change "driven" to -drive--.

Column 12, line 8; change "for" to --of.

Column 12, line 9; change "driven" to drive.

Column 12, line 14; after "light" insert --means.

Signed and Scaled this ninth D3) of March 1976 [SEAL] Attest:

RUTH c. MASON c. MARSHALL DANN Allestr'ng Officer Commissioner nflarems and Trademarks 

1. In a thread supply device for a textile machine having a drive, the thread supply device including a thread drum to which the thread may be supplied tangentially, a winding drive for loading the thread on the drum, a thread conTrol element which is movable into first and second positions, in which first position the thread is removable axially of the drum at a speed independent of the winding speed so as to permit intermittent thread supply and in which second position the removal speed of the thread from the drum is limited to the winding speed so as to permit positive thread supply, switch means actuable by said thread control element for continuously actuating the winding drive when said control element is in the second position, and sensing means for monitoring the thread supply on the thread drum and for disconnecting the winding drive when the control element is in the first position and a preselected amount of thread is present on the thread drum, comprising the improvement wherein the switch means is an electrical double-throw switch which is disposed in a first switching position during intermittent thread supply and is disposed in a second switching position during positive thread supply, and said sensing means being switched into a circuit by means of the double-throw switch during positive thread supply such that a control circuit causes deenergization of the machine drive when the thread storage on the thread drum differs in one direction from the preselected amount.
 2. A thread supply device according to claim 1, in which the preselected amount comprises a preselected maximum thread storage so that the machine drive is deenergized during positive thread supply when the preselected maximum thread storage is exceeded, the sensing means containing a sensing switch connected in series with the double-throw switch, the series circuit formed from the sensing switch and from the first route of the double throw switch when same is in said first switching position during intermittent thread supply being connected to a thread drum control circuit for the winding drive, said thread drum control circuit deenergizing the winding drive when the double throw switch is in said first switching position and the sensing switch is closed due to the thread supply on the drum exceeding said maximum thread storage, and the series circuit formed from the sensing switch and from a second route of the double-throw switch when same is in said second switching position during positive thread supply being connected to the control circuit of the machine drive whereby the machine drive is deenergized due to closing of said sensing switch when the thread supply on said drum exceeds said preselected maximum thread storage.
 3. A thread supply device according to claim 2, wherein the thread control element is designed as a thread hook which can be pivoted into the path of movement of thread which is unwound from the drum in the axial direction thereof, said hook having an opened end such that the thread is caught in the hook during positive thread supply from the drum.
 4. A thread device according to claim 1, in which the preselected amount comprises a preselected minimum thread storage so that the machine drive is deactivated during positive thread supply when the thread supply falls below said preselected minimum thread storage, the sensing means containing a sensing switch connected in series with the double-throw switch, the series circuit formed from the sensing switch and from the first route of the double-throw switch when same is in said first switching position during intermittent thread supply being connected to a thread drum control circuit for the winding drive, said thread drum control circuit energizing the winding drive when the double-throw switch is in said first switching position and the sensing switch is closed due to the thread supply on the drum falling below said minimum thread storage, and the series circuit formed from the sensing switch and from a second route of the double-throw switch when same is in said second switching position during positive thread supply being connected to the control circuit of the machine drive whereby the machine drive is deenergized due to closing of said sensinG switch when the thread supply on said drum falls below said minimum thread storage.
 5. A thread supply device according to claim 1, wherein said preselected amount comprises both a preselected maximum thread storage and a preselected minimum thread storage, said sensing means including a first sensing switch which responds when the maximum thread storage is obtained on the drum and a second sensing switch which responds when the minimum thread storage is obtained on the drum, only one of said sensing switches being connected in series with a first route of the double-throw switch when same is in said first switching position, said first route being connected to the winding drive, and both of said sensing switches being connected in series with a second route of the double throw switch when same is in the second switching position during positive thread supply, the second route of the double-throw switch being interconnected to the machine drive so as to deenergize the machine drive when the thread storage on the drum exceeds or falls below the maximum or minimum thread storage, respectively.
 6. A thread supply device according to claim 5, wherein the double-throw switch includes two poles, first and second sensing switches being disposed in parallel and each connected in series with one of said poles, and the two parallel circuits formed by said sensing switches each being connected in series with the control circuit for the machine drive when the double-throw switch is in said second switching position.
 7. A thread supply device according to claim 1, including thread monitor means associated with the thread which is being unwound from said drum for sensing a breakage in said thread, said thread monitor means including a monitoring switch which is closed when a break in the thread occurs, said monitoring switch being interconnected to the machine drive for deenergizing same when the monitoring switch is closed.
 8. A thread supply device according to claim 1, including thread monitor means associated with the thread which is being wound onto said drum for sensing a breakage in said thread, said thread monitor means including a monitoring switch which is closed when a break in the thread occurs, said monitoring switch being interconnected to the machine driven for deenergizing same when the monitoring switch is closed.
 9. A thread supply device according to claim 1, wherein the control circuit for the machine drive is formed by a relay which maintains the machine driven in operation so long as the relay is in a currentness state.
 10. A thread supply device according to claim 1, including signal light means energizable when the machine drive is deenergized, the signal light being connected in circuit with the double-throw switch when same is in the second switching position. 